Image sensors have become ubiquitous. They are widely used in digital still cameras, cellular phones, security cameras, as well as, medical, automobile and other applications. The technology used to manufacture image sensors, and in particular complementary metal-oxide semiconductor (“CMOS”) image sensor, has continued to advance at a great pace. For example, image sensors are increasingly higher resolution, lower power, and have better light sensitivity.
In image sensors, and in many other kinds of electronics, power supplies that are both stable and efficient are advantageous. Additionally, power supplies with low noise can be especially advantageous in electronics with sensors, including image sensors. In image sensors, the image quality of an image produced by the image sensor may be especially dependent on a low noise power supply. In particular, image sensors with lower noise power supplies may have better dynamic range, which can assist photographers in capturing images in low light environments. Furthermore, a low noise power supply reduces the burden on designers and manufacturers to include complicated filtering circuits to filter out noise introduced by power supplies. Since image sensors are also commonplace in mobile devices with limited power resources, the efficiency of an image sensor and the power supplies included in or supplying the image sensor are increasingly important to preserving battery life in mobile devices.